What is 7,200,000 written in scientific notation?
A7.2 x 10^3
B7.2 x 10^4
C7.2 x 10^5
D7.2 x 10^6
A7.2 x 10^3
B7.2 x 10^4
C7.2 x 10^5
D7.2 x 10^6
